And with that buildup, Boardwalk Empire executed one of the most surprising moves in recent TV history: killing off James “Jimmy” Darmody (Michael Pitt), the show’s second-biggest character after Enoch “Nucky” Thompson (Steve Buscemi).

Nucky shot and killed his former protégé after a season-long power struggle for control of the Atlantic City booze trade. The Oedipal-conflicted young war veteran was the victim of his own tragic decisions, including a bungled assassination attempt on Nucky. Though many fans will regret losing Pitt’s character, the move gave viewers an uncompromising finale that allows Nucky to embrace his gangster destiny.

Below, Boardwalk Empire showrunner and executive producer Terence Winter, who wrote tonight’s finale, talks to EW about why Jimmy had to go, how he broke the news to Pitt and gives some hints about his plans for season 3 — which include a time jump and the introduction of new brash young character. And at the end of the interview, there’s a link to our exclusive interview with Pitt.

ENTERTAINMENT WEEKLY:When did you first know that you were going to kill off Jimmy?

TERENCE WINTER: Probably at the very beginning of season 2. The idea was to try and push things to their absolute limit, even if it makes it difficult for yourself and your writing team. If you take things to their logical extreme with the situation we created, Jimmy has betrayed Nucky, he tried to have him killed. You want to be honest about the storytelling. In the pilot, Jimmy told Nucky: “You can’t be half a gangster anymore.” We wanted with the first two seasons to follow that trajectory, where he goes full season from being the guy who doesn’t want to get his hands dirty to actually pulling the trigger himself. And what’s the strongest version of that? To pull the trigger on the very guy who told him, “You can’t be half a gangster anymore.” It’s like, “Guess what? You’re right. I can’t. And here’s me now fully becoming a gangster.” Anything short of Nucky doing it himself wouldn’t feel real, it wouldn’t be real. And it would be a cheat for us to say, “We want to keep our beloved character Jimmy Darmody alive.”

One of the things I wanted to do by design in the finale is make the audience pissed off [at the start of the episode]. I wanted people to say [when it seemed like Nucky and Jimmy would reconcile], “Oh great, after all that, it’s all going to be forgotten and Jimmy is going to be back in Nucky’s good graces.” I wanted them to think right up to the very end that Nucky is going to forgive him and take him back. It was a really hard decision. You’re sort of blowing up your own show, in some ways. Now we’re back in the writers room trying to figure out where we go from here without Jimmy Darmody.

My only concern plot-wise was wondering whether Jimmy would really go so willingly to what he likely believes is his death.

We know with [the previous week’s episode] that he’s so emotionally damaged. I don’t think Jimmy ever expected to come back alive from World War I. I think he probably left for the war hoping he would die and was surprised he survived. He’s been a walking dead person ever since we’ve met him. He’s come back and gone through the motions of a person trying to make his way in the world, but ultimately becomes resigned to his fate. He gets manipulated into this run against Nucky, who was his mentor, and really the only father figure of any meaning that he has. The plot failed and he knows, as a good solider, he’s going to have to fall on his sword. He fully knows what he’s walking into at the end. He’s not armed. He says goodbye to his son. He basically gives Richard Harrow permission to not come with him. He knows he needs to be punished. The circumstances of his life have unraveled to the point where he’s willing to accept his fate. And psychologically Harrow is prepared to respect that as a soldier.

You touch on this in that last answer, but I still wanted to ask: Especially in light of what happens this week, why was it important to have the flashback that included the scene of Jimmy having sex with his mom?

We wanted to answer the questions: Why were Jimmy and Angela together in the first place? What is the basis of this weird relationship with his mother? What’s this strange hold she has on him? From the very first moment you see Jimmy and his mother together it’s really inappropriate — you think it’s a girlfriend, then you learn it’s his mother. We just wanted to pay that story off. It gives us so much insight into Jimmy’s psychology and how things got to this point.

I’m still haunted by his mom’s “I used to kiss his little winky” line from the season premiere.

Exactly.

On The Sopranos, you guys killed off plenty of key roles — you wrote the amazing “Long Term Parking” episode (where Adriana died). Arguably, this is a bigger move than any Sopranos hit. Do you have any concern about losing such a popular character?

Huge concern. As we go about the business of TV, you’re constantly looking for ways to keep ahead of the audience or defy expectations. It’s a big gamble creatively, you’re killing off a major, major character very early on. But you want to be true to the story and to do the most unexpected thing. The audience is used to seeing bodies start to drop in season 5. People won’t believe [Jimmy’s dead] until the last second and even then some will wonder if it’s a dream. People didn’t believe it when Adriana was killed on The Sopranos and that was in season 5.

Because so many people thought Adriana was still alive, I was wondering if that’s why you showed Jimmy’s gunshot wounds.

That wasn’t conscious, but it never hurts to be definitive. He’s not getting up.

When did you tell Michael and how did that go?

We talked about it during the year. I generally don’t like to give actors a lot of advance notice about what’s happening on the show, because what [the writers] think is going to happen can change. The other thing is a lot of actors don’t want to know what’s coming. If they know the future of their characters, that information might [influence] their performance.

Michael saw the way it was shaping up and he came into my office and he was all, “Are you guys considering where this is heading? Is Eli going to die? Have you thought about killing me?” And I said, “Yeah, we actually have. All I will tell you is everything is on the table. It could go this way, it could go that way. I don’t know.” Up until episode 9, I wasn’t 100 percent sure this is where we were going to go. I was pretty sure. I wanted to reserve my right to change my mind up until the last minute so I didn’t want to tell him. So he didn’t know officially until right before the script for [the finale] came out. He had a very strong suspicion and I was certainly preparing him for it. But Michael is an artist. He’s a phenomenal actor, and part of the challenge is to keep reinventing the series. He’s very much about doing what’s best for the show and the character. In terms of the storytelling, he totally got it. He really loved doing the show, but he’s also a guy who likes to do different things. I think he understands this was the single most powerful thing you could have done on the show.

Was that a slight Godfather nod, cross-cutting the wedding and the whacking?

Yeah, always. I’m not ashamed to say Godfather is one of my favorite movies of all time, and any time I can steal from it, I always do.

With Van Alden having run off to Cicero, is he going to still be in our story?

Yeah. People who are really students of Mob history will pick up on the fact that Cicero, Ill., is the place Al Capone became headquartered in 1924. So we put him in a place where he theoretically could interact with other characters on the show.

So can we expect to see Al Capone come into his own as a formidable force next season?

As time goes on. The plan is now is we would come back in season 3 a little further into the future and start to really track Al Capone’s rise and — God willing — through the course of the series. By 1925, Capone was the guy everybody recognizes — the guy in the white fedora who’s firmly in charge of Chicago. Hopefully we’ll be on the air long enough to see that guy. Certainly in [season 3] we’ll start to see Capone on pretty much equal footing as Johnny Torrio in terms of who’s running the town.

You mentioned jumping forward in time for season 3. How long will that be? [Note: Season 2 was set in 1921]

We’re thinking about 16 months and starting the [third] season around the beginning of 1923, then maybe run through the end of 1923. It was an exciting year. All the people who stockpiled liquor started to run out, so competition between bootleggers became really fierce.

I can’t imagine Nucky is going to be very pleased with Margaret donating all his land to the church.

I don’t think that will make anybody happy. The ramifications of that will be explored as the series progresses.

And I’m assuming Richard Harrow will continue as a key player?

Yes, Harrow will continue to be part of the show, absolutely.

One thing that impacted me this season was the polio story line — a really heartbreaking move. It’s easy to forget nowadays what a horrible disease that was.

Especially with that little girl. That actress is really so sweet. It was hard for us. My wife read that script and punched me in the arm. Steve Buscemi read the script and said he threw it across the room. We did a lot of research on the subject and it just ravaged children in this country, and adults too. It was a horrific disease.

So for season 3, I hear you’re looking to add a new character, Bud Matheson, described as a young James Cagney type. Might that be Boardwalk‘s new up-and-comer?

Yeah. As the ’20s progressed and became the Roaring ’20s, it was very youth-oriented culture. Young people really came into their own, with access to automobiles. They had influence on popular music and fashion trends. We really wanted to infuse the show with some exciting young sexy energy and this guy is the sort of embodiment of that new sort of go-getter who wants to grasp things with both hands. Cagney was a great prototype — the fast-talking brash young guy who wants it all and wants it now.